/*
 * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 2001-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.sun.org.apache.xerces.internal.parsers;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Locale;

import com.sun.org.apache.xerces.internal.impl.Constants;
import com.sun.org.apache.xerces.internal.util.FeatureState;
import com.sun.org.apache.xerces.internal.util.ParserConfigurationSettings;
import com.sun.org.apache.xerces.internal.util.PropertyState;
import com.sun.org.apache.xerces.internal.util.Status;
import com.sun.org.apache.xerces.internal.util.SymbolTable;
import com.sun.org.apache.xerces.internal.xni.XMLDTDContentModelHandler;
import com.sun.org.apache.xerces.internal.xni.XMLDTDHandler;
import com.sun.org.apache.xerces.internal.xni.XMLDocumentHandler;
import com.sun.org.apache.xerces.internal.xni.XNIException;
import com.sun.org.apache.xerces.internal.xni.parser.XMLComponent;
import com.sun.org.apache.xerces.internal.xni.parser.XMLComponentManager;
import com.sun.org.apache.xerces.internal.xni.parser.XMLConfigurationException;
import com.sun.org.apache.xerces.internal.xni.parser.XMLDocumentSource;
import com.sun.org.apache.xerces.internal.xni.parser.XMLEntityResolver;
import com.sun.org.apache.xerces.internal.xni.parser.XMLErrorHandler;
import com.sun.org.apache.xerces.internal.xni.parser.XMLInputSource;
import com.sun.org.apache.xerces.internal.xni.parser.XMLParserConfiguration;

/**
 * A very basic parser configuration. This configuration class can
 * be used as a base class for custom parser configurations. The
 * basic parser configuration creates the symbol table (if not
 * specified at construction time) and manages all of the recognized
 * features and properties.
 * <p>
 * The basic parser configuration does <strong>not</strong> mandate
 * any particular pipeline configuration or the use of specific
 * components except for the symbol table. If even this is too much
 * for a basic parser configuration, the programmer can create a new
 * configuration class that implements the
 * <code>XMLParserConfiguration</code> interface.
 * <p>
 * Subclasses of the basic parser configuration can add their own
 * recognized features and properties by calling the
 * <code>addRecognizedFeature</code> and
 * <code>addRecognizedProperty</code> methods, respectively.
 * <p>
 * The basic parser configuration assumes that the configuration
 * will be made up of various parser components that implement the
 * <code>XMLComponent</code> interface. If subclasses of this
 * configuration create their own components for use in the
 * parser configuration, then each component should be added to
 * the list of components by calling the <code>addComponent</code>
 * method. The basic parser configuration will make sure to call
 * the <code>reset</code> method of each registered component
 * before parsing an instance document.
 * <p>
 * This class recognizes the following features and properties:
 * <ul>
 * <li>Features
 * <ul>
 * <li>http://xml.org/sax/features/validation</li>
 * <li>http://xml.org/sax/features/namespaces</li>
 * <li>http://xml.org/sax/features/external-general-entities</li>
 * <li>http://xml.org/sax/features/external-parameter-entities</li>
 * </ul>
 * <li>Properties
 * <ul>
 * <li>http://xml.org/sax/properties/xml-string</li>
 * <li>http://apache.org/xml/properties/internal/symbol-table</li>
 * <li>http://apache.org/xml/properties/internal/error-handler</li>
 * <li>http://apache.org/xml/properties/internal/entity-resolver</li>
 * </ul>
 * </ul>
 *
 * @author Arnaud  Le Hors, IBM
 * @author Andy Clark, IBM
 * @version $Id: BasicParserConfiguration.java,v 1.6 2010-11-01 04:40:09 joehw Exp $
 */
public abstract class BasicParserConfiguration
    extends ParserConfigurationSettings
    implements XMLParserConfiguration {

  //
  // Constants
  //

  // feature identifiers

  /**
   * Feature identifier: validation.
   */
  protected static final String VALIDATION =
      Constants.SAX_FEATURE_PREFIX + Constants.VALIDATION_FEATURE;

  /**
   * Feature identifier: namespaces.
   */
  protected static final String NAMESPACES =
      Constants.SAX_FEATURE_PREFIX + Constants.NAMESPACES_FEATURE;

  /**
   * Feature identifier: external general entities.
   */
  protected static final String EXTERNAL_GENERAL_ENTITIES =
      Constants.SAX_FEATURE_PREFIX + Constants.EXTERNAL_GENERAL_ENTITIES_FEATURE;

  /**
   * Feature identifier: external parameter entities.
   */
  protected static final String EXTERNAL_PARAMETER_ENTITIES =
      Constants.SAX_FEATURE_PREFIX + Constants.EXTERNAL_PARAMETER_ENTITIES_FEATURE;

  // property identifiers

  /**
   * Property identifier: xml string.
   */
  protected static final String XML_STRING =
      Constants.SAX_PROPERTY_PREFIX + Constants.XML_STRING_PROPERTY;

  /**
   * Property identifier: symbol table.
   */
  protected static final String SYMBOL_TABLE =
      Constants.XERCES_PROPERTY_PREFIX + Constants.SYMBOL_TABLE_PROPERTY;

  /**
   * Property identifier: error handler.
   */
  protected static final String ERROR_HANDLER =
      Constants.XERCES_PROPERTY_PREFIX + Constants.ERROR_HANDLER_PROPERTY;

  /**
   * Property identifier: entity resolver.
   */
  protected static final String ENTITY_RESOLVER =
      Constants.XERCES_PROPERTY_PREFIX + Constants.ENTITY_RESOLVER_PROPERTY;

  //
  // Data
  //

  // components (non-configurable)

  /**
   * Symbol table.
   */
  protected SymbolTable fSymbolTable;

  // data

  /**
   * Locale.
   */
  protected Locale fLocale;

  /**
   * Components.
   */
  protected ArrayList fComponents;

  // handlers

  /**
   * The document handler.
   */
  protected XMLDocumentHandler fDocumentHandler;

  /**
   * The DTD handler.
   */
  protected XMLDTDHandler fDTDHandler;

  /**
   * The DTD content model handler.
   */
  protected XMLDTDContentModelHandler fDTDContentModelHandler;

  /**
   * Last component in the document pipeline
   */
  protected XMLDocumentSource fLastComponent;

  //
  // Constructors
  //

  /**
   * Default Constructor.
   */
  protected BasicParserConfiguration() {
    this(null, null);
  } // <init>()

  /**
   * Constructs a parser configuration using the specified symbol table.
   *
   * @param symbolTable The symbol table to use.
   */
  protected BasicParserConfiguration(SymbolTable symbolTable) {
    this(symbolTable, null);
  } // <init>(SymbolTable)

  /**
   * Constructs a parser configuration using the specified symbol table
   * and parent settings.
   *
   * @param symbolTable The symbol table to use.
   * @param parentSettings The parent settings.
   */
  protected BasicParserConfiguration(SymbolTable symbolTable,
      XMLComponentManager parentSettings) {
    super(parentSettings);

    // create a vector to hold all the components in use
    fComponents = new ArrayList();

    // create table for features and properties
    fFeatures = new HashMap();
    fProperties = new HashMap();

    // add default recognized features
    final String[] recognizedFeatures = {
        PARSER_SETTINGS,
        VALIDATION,
        NAMESPACES,
        EXTERNAL_GENERAL_ENTITIES,
        EXTERNAL_PARAMETER_ENTITIES,
    };
    addRecognizedFeatures(recognizedFeatures);
    fFeatures.put(PARSER_SETTINGS, Boolean.TRUE);
    // set state for default features
    fFeatures.put(VALIDATION, Boolean.FALSE);
    fFeatures.put(NAMESPACES, Boolean.TRUE);
    fFeatures.put(EXTERNAL_GENERAL_ENTITIES, Boolean.TRUE);
    fFeatures.put(EXTERNAL_PARAMETER_ENTITIES, Boolean.TRUE);

    // add default recognized properties
    final String[] recognizedProperties = {
        XML_STRING,
        SYMBOL_TABLE,
        ERROR_HANDLER,
        ENTITY_RESOLVER,
    };
    addRecognizedProperties(recognizedProperties);

    if (symbolTable == null) {
      symbolTable = new SymbolTable();
    }
    fSymbolTable = symbolTable;
    fProperties.put(SYMBOL_TABLE, fSymbolTable);

  } // <init>(SymbolTable)

  /**
   * Adds a component to the parser configuration. This method will
   * also add all of the component's recognized features and properties
   * to the list of default recognized features and properties.
   *
   * @param component The component to add.
   */
  protected void addComponent(XMLComponent component) {

    // don't add a component more than once
    if (fComponents.contains(component)) {
      return;
    }
    fComponents.add(component);

    // register component's recognized features
    String[] recognizedFeatures = component.getRecognizedFeatures();
    addRecognizedFeatures(recognizedFeatures);

    // register component's recognized properties
    String[] recognizedProperties = component.getRecognizedProperties();
    addRecognizedProperties(recognizedProperties);

    // set default values
    if (recognizedFeatures != null) {
      for (int i = 0; i < recognizedFeatures.length; i++) {
        String featureId = recognizedFeatures[i];
        Boolean state = component.getFeatureDefault(featureId);
        if (state != null) {
          super.setFeature(featureId, state.booleanValue());
        }
      }
    }
    if (recognizedProperties != null) {
      for (int i = 0; i < recognizedProperties.length; i++) {
        String propertyId = recognizedProperties[i];
        Object value = component.getPropertyDefault(propertyId);
        if (value != null) {
          super.setProperty(propertyId, value);
        }
      }
    }

  } // addComponent(XMLComponent)

  //
  // XMLParserConfiguration methods
  //

  /**
   * Parse an XML document.
   * <p>
   * The parser can use this method to instruct this configuration
   * to begin parsing an XML document from any valid input source
   * (a character stream, a byte stream, or a URI).
   * <p>
   * Parsers may not invoke this method while a parse is in progress.
   * Once a parse is complete, the parser may then parse another XML
   * document.
   * <p>
   * This method is synchronous: it will not return until parsing
   * has ended.  If a client application wants to terminate
   * parsing early, it should throw an exception.
   *
   * @param inputSource The input source for the top-level of the XML document.
   * @throws XNIException Any XNI exception, possibly wrapping another exception.
   * @throws IOException An IO exception from the parser, possibly from a byte stream or character
   * stream supplied by the parser.
   */
  public abstract void parse(XMLInputSource inputSource)
      throws XNIException, IOException;

  /**
   * Sets the document handler on the last component in the pipeline
   * to receive information about the document.
   *
   * @param documentHandler The document handler.
   */
  public void setDocumentHandler(XMLDocumentHandler documentHandler) {
    fDocumentHandler = documentHandler;
    if (fLastComponent != null) {
      fLastComponent.setDocumentHandler(fDocumentHandler);
      if (fDocumentHandler != null) {
        fDocumentHandler.setDocumentSource(fLastComponent);
      }
    }
  } // setDocumentHandler(XMLDocumentHandler)

  /**
   * Returns the registered document handler.
   */
  public XMLDocumentHandler getDocumentHandler() {
    return fDocumentHandler;
  } // getDocumentHandler():XMLDocumentHandler

  /**
   * Sets the DTD handler.
   *
   * @param dtdHandler The DTD handler.
   */
  public void setDTDHandler(XMLDTDHandler dtdHandler) {
    fDTDHandler = dtdHandler;
  } // setDTDHandler(XMLDTDHandler)

  /**
   * Returns the registered DTD handler.
   */
  public XMLDTDHandler getDTDHandler() {
    return fDTDHandler;
  } // getDTDHandler():XMLDTDHandler

  /**
   * Sets the DTD content model handler.
   *
   * @param handler The DTD content model handler.
   */
  public void setDTDContentModelHandler(XMLDTDContentModelHandler handler) {
    fDTDContentModelHandler = handler;
  } // setDTDContentModelHandler(XMLDTDContentModelHandler)

  /**
   * Returns the registered DTD content model handler.
   */
  public XMLDTDContentModelHandler getDTDContentModelHandler() {
    return fDTDContentModelHandler;
  } // getDTDContentModelHandler():XMLDTDContentModelHandler

  /**
   * Sets the resolver used to resolve external entities. The EntityResolver
   * interface supports resolution of public and system identifiers.
   *
   * @param resolver The new entity resolver. Passing a null value will uninstall the currently
   * installed resolver.
   */
  public void setEntityResolver(XMLEntityResolver resolver) {
    // REVISIT: Should this be a property?
    fProperties.put(ENTITY_RESOLVER, resolver);
  } // setEntityResolver(XMLEntityResolver)

  /**
   * Return the current entity resolver.
   *
   * @return The current entity resolver, or null if none has been registered.
   * @see #setEntityResolver
   */
  public XMLEntityResolver getEntityResolver() {
    // REVISIT: Should this be a property?
    return (XMLEntityResolver) fProperties.get(ENTITY_RESOLVER);
  } // getEntityResolver():XMLEntityResolver

  /**
   * Allow an application to register an error event handler.
   *
   * <p>If the application does not register an error handler, all
   * error events reported by the SAX parser will be silently
   * ignored; however, normal processing may not continue.  It is
   * highly recommended that all SAX applications implement an
   * error handler to avoid unexpected bugs.</p>
   *
   * <p>Applications may register a new or different handler in the
   * middle of a parse, and the SAX parser must begin using the new
   * handler immediately.</p>
   *
   * @param errorHandler The error handler.
   * @throws java.lang.NullPointerException If the handler argument is null.
   * @see #getErrorHandler
   */
  public void setErrorHandler(XMLErrorHandler errorHandler) {
    // REVISIT: Should this be a property?
    fProperties.put(ERROR_HANDLER, errorHandler);
  } // setErrorHandler(XMLErrorHandler)

  /**
   * Return the current error handler.
   *
   * @return The current error handler, or null if none has been registered.
   * @see #setErrorHandler
   */
  public XMLErrorHandler getErrorHandler() {
    // REVISIT: Should this be a property?
    return (XMLErrorHandler) fProperties.get(ERROR_HANDLER);
  } // getErrorHandler():XMLErrorHandler

  /**
   * Set the state of a feature.
   *
   * Set the state of any feature in a SAX2 parser.  The parser
   * might not recognize the feature, and if it does recognize
   * it, it might not be able to fulfill the request.
   *
   * @param featureId The unique identifier (URI) of the feature.
   * @param state The requested state of the feature (true or false).
   * @throws com.sun.org.apache.xerces.internal.xni.parser.XMLConfigurationException If the
   * requested feature is not known.
   */
  public void setFeature(String featureId, boolean state)
      throws XMLConfigurationException {

    // forward to every component
    int count = fComponents.size();
    for (int i = 0; i < count; i++) {
      XMLComponent c = (XMLComponent) fComponents.get(i);
      c.setFeature(featureId, state);
    }
    // save state if noone "objects"
    super.setFeature(featureId, state);

  } // setFeature(String,boolean)

  /**
   * setProperty
   */
  public void setProperty(String propertyId, Object value)
      throws XMLConfigurationException {

    // forward to every component
    int count = fComponents.size();
    for (int i = 0; i < count; i++) {
      XMLComponent c = (XMLComponent) fComponents.get(i);
      c.setProperty(propertyId, value);
    }

    // store value if noone "objects"
    super.setProperty(propertyId, value);

  } // setProperty(String,Object)

  /**
   * Set the locale to use for messages.
   *
   * @param locale The locale object to use for localization of messages.
   * @throws XNIException Thrown if the parser does not support the specified locale.
   */
  public void setLocale(Locale locale) throws XNIException {
    fLocale = locale;
  } // setLocale(Locale)

  /**
   * Returns the locale.
   */
  public Locale getLocale() {
    return fLocale;
  } // getLocale():Locale

  //
  // Protected methods
  //

  /**
   * reset all components before parsing and namespace context
   */
  protected void reset() throws XNIException {

    // reset every component
    int count = fComponents.size();
    for (int i = 0; i < count; i++) {
      XMLComponent c = (XMLComponent) fComponents.get(i);
      c.reset(this);
    }

  } // reset()

  /**
   * Check a property. If the property is known and supported, this method
   * simply returns. Otherwise, the appropriate exception is thrown.
   *
   * @param propertyId The unique identifier (URI) of the property being set.
   * @throws com.sun.org.apache.xerces.internal.xni.parser.XMLConfigurationException If the
   * requested feature is not known or supported.
   */
  protected PropertyState checkProperty(String propertyId)
      throws XMLConfigurationException {

    // special cases
    if (propertyId.startsWith(Constants.SAX_PROPERTY_PREFIX)) {
      final int suffixLength = propertyId.length() - Constants.SAX_PROPERTY_PREFIX.length();

      //
      // http://xml.org/sax/properties/xml-string
      // Value type: String
      // Access: read-only
      //   Get the literal string of characters associated with the
      //   current event.  If the parser recognises and supports this
      //   property but is not currently parsing text, it should return
      //   null (this is a good way to check for availability before the
      //   parse begins).
      //
      if (suffixLength == Constants.XML_STRING_PROPERTY.length() &&
          propertyId.endsWith(Constants.XML_STRING_PROPERTY)) {
        // REVISIT - we should probably ask xml-dev for a precise
        // definition of what this is actually supposed to return, and
        // in exactly which circumstances.
        return PropertyState.NOT_SUPPORTED;
      }
    }

    // check property
    return super.checkProperty(propertyId);

  } // checkProperty(String)


  /**
   * Check a feature. If feature is know and supported, this method simply
   * returns. Otherwise, the appropriate exception is thrown.
   *
   * @param featureId The unique identifier (URI) of the feature.
   * @throws XMLConfigurationException Thrown for configuration error. In general, components should
   * only throw this exception if it is <strong>really</strong> a critical error.
   */
  protected FeatureState checkFeature(String featureId)
      throws XMLConfigurationException {

    //
    // Xerces Features
    //
    if (featureId.startsWith(Constants.XERCES_FEATURE_PREFIX)) {
      final int suffixLength = featureId.length() - Constants.XERCES_FEATURE_PREFIX.length();

      //
      // special performance feature: no one by component manager is allowed to set it
      //
      if (suffixLength == Constants.PARSER_SETTINGS.length() &&
          featureId.endsWith(Constants.PARSER_SETTINGS)) {
        return FeatureState.NOT_SUPPORTED;
      }
    }

    return super.checkFeature(featureId);
  } // checkFeature(String)


} // class BasicParserConfiguration
